Designed synthesis of titania nanoparticles coated hierarchially ordered macro/mesoporous silica for selective enrichment of phosphopeptides.

Metal oxide affinity chromatography (MOAC) is a powerful technique in phosphoproteome research. However, the achievement of highly specific enrichment and sensitive detection of phosphopeptide by MOAC remains a big challenge since the lack of high specificity and large binding capacity of conventional MOAC materials. In this work, a new MOAC material, TiO2-coated hierarchically ordered macro/mesoporous silica (denoted as HOMMS@TiO2) composites, was prepared via a facile process. The HOMMS@TiO2 composites were demonstrated to have low limit of detection (8 fmol) and great specificity with a very rapid enrichment speed (within 1 min). These experimental results have demonstrated that the HOMMS@TiO2 exhibit great potential in phosphoproteome research.